An ANP-based approach for the selection of photovoltaic solar power plant investment projects

In this paper the Analytic Network Process (ANP) is applied to the selection of photovoltaic (PV) solar power projects. These projects follow a long management and execution process from plant site selection to plant start-up. As a consequence, there are many risks of time delays and even of project stoppage.In the case study presented in this paper a top manager of an important Spanish company that operates in the power market has to decide on the best PV project (from four alternative projects) to invest based on risk minimization. The manager identified 50 project execution delay and/or stoppage risks.The influences between the elements of the network (groups of risks and alternatives) were identified and analyzed using the ANP multicriteria decision analysis method. Two different ANP models were used: one hierarchy model (that considers AHP as a particular case of ANP) and one network-based model. The results obtained in each model were compared and analyzed. The main conclusion is that unlike the other models used in the study, the single network model can manage all the information of the real-world problem and thus it is the decision analysis model recommended by the authors. The strengths and weaknesses of ANP as a multicriteria decision analysis tool are also described in the paper.     

Factors in determining wind farm location: Integrating GQM,fuzzy DEMATEL,and ANP

Wind power has become one of the most popular sources of renewable energy, and various countries have increased their use of wind turbines because of turbines' rapid and relatively simple installation. This study examines the key factors considered in determining the location of wind farms. The following six dimensions are used to measure the correlations among the relevant factors: Safety and Quality, Economy and Benefit, Social Impression, Environment and Ecology, Regulation, and Policy. These factors are associated with a total of 28 evaluation criteria. The Decision Making Trial and Evaluation Laboratory (DEMATEL) and Analytic Network Process (ANP) approaches are applied to find the correlations among the dimensions and the relative weights of the criteria, respectively. The results show that Safety and Quality and Environment and Ecology are the two major factors. The results of this work can increase public understanding of wind power and can be used as a reference for businesses and governments that intend to invest in the development of such power.     

Biomass gasifier projects for decentralized power supply in India: A financial evaluation

Results of a techno-economic evaluation of biomass gasifier based projects for decentralized power supply for remote locations in India are presented. Contributions of different components of diesel engine generator (DG) sets, dual fuel (DF) engine generator sets and 100% producer gas (HPG) engine generator sets to their capital costs as well as to the levelized unit cost of electricity (LUCE) delivered by the same have been analyzed. LUCE delivered to the consumers has been estimated to be varying in the range of Rs. 13.14–24.49/kWh (US$¹ 0.30–0.55/kWh) for DF BGPP. LUCE increases significantly if BGPP is operated at part loads. Presently available 40 kW capacity HPG systems in India are expected to be financially competitive with a DG set of equivalent capacity beyond a break-even diesel price of Rs. 34.70/l. It is expected to be financially more attractive than an equivalent capacity DF BGPP for diesel prices of more than Rs. 44.29/l. In certain specific conditions operating two smaller capacity systems has been found to be attractive as against a single larger capacity system.     

生物质气化工艺及装置研究进展

文章分析了生物质气化技术的发展现状,介绍了几种典型的生物质气化工艺及装置,比较了固定床、流化床等气化装置的优缺点,并分析了现有气化工艺存在的问题以及生物质热解气化技术的发展前景。     

核电项目投资风险评价指标体系构建

核电项目往往具有投资大、周期长、技术复杂的特点,并且投资回报具有不可预见性和不确定性,因此对核电项目进行风险评价具有重要意义。分析了政治风险、法律风险、自然环境风险、经济风险、管理风险、安全风险、财务风险等核电项目风险因素的特点。在借鉴国内外研究成果的基础上,结合核电项目的特点,建立了核电项目的投资风险评价指标体系。设计了涵盖了7个一级指标、19个二级指标的调查问卷。指标的测量均采用李克特5级打分法。利用SPSS20．0统计分析软件对问卷数据进行分析。根据评价指标对核电项目投资风险影响程度的统计分析结果,剔除了与项目相关性不明显的两个指标。对修正后的指标体系进行因子分析后,共提取7个公因子,最终构建了一个包括政策法律风险、安全风险、经济风险、管理风险、技术风险、财务风险和人员风险7个一级指标和政策法规健全程度、政策法规的稳定性等17个二级指标的核电项目投资风险评价指标体系。     

电力建设项目风险评价研究

对电力建设项目存在的风险进行了系统识别,建立了电力建设项目风险评价指标体系,提出,电力建设项目风险评价的适用方法。     

Objective and subjective evaluation of power plants and their non-radioactive emissions using the analytic hierarchy process

Non-nuclear power plant emissions are of great concern to the public and to scientists alike. As energy demand tends to rise rapidly, especially in the developing countries, the negative effects to human health and to the environment from gaseous emissions together with hazardous particulate matter released by power plants can no longer be ignored.     

Technological,economic and sustainability evaluation of power plants using the Analytic Hierarchy Process

Complexity of power plant evaluation is steadily rising, as more criteria are involved in the overall assessment while evaluation data change rapidly. Apart from evaluating several aspects of power plants separately, a multicriteria analysis based on hierarchically structured criteria is necessary, so as to address the overall assessment of power plants according to the technological, economic and sustainability aspects. For this reason, in this paper, ten types of power plant are evaluated using nine end node criteria properly structured under the Analytical Hierarchy Process. Moreover, pairwise comparisons allow for accurate subjective criteria weighting.     

An Analytic Hierarchy Process to evaluate PEM fuel cell engine performance

An evaluation model of PEM fuel cell engine (FCE) performance is developed, which provides a new method for a quantitative assessment of FCE performance. Some basic properties and their sub-performance indexes are proposed to evaluate overall performance by analyzing FCE properties, and then the Analytic Hierarchy Process (AHP) theory is used to obtain weighted values of the indexes. Proper scoring functions are established to convert the index values into scores and finally we get an overall score of FCE performance. An example for a real FCE evaluation is also given to illustrate the method.     

火电站建设工程中工程造价的控制

叙述了火电站建设的现状,指出,控制工程造价的必要性。总结了火电站建设工程的3个阶段,探讨了项目实施过程中的可能存在的问题,认为,只有进行全过程、全方位的管理和控制,才能有效地控制工程造价,最大程度的获取投资效益。     

Separation technology–Making a difference in biorefineries

In the quest for a sustainable bio-based economy, biorefineries play a central role as they involve the sustainable processing of biomass into marketable products and energy. This paper aims to provide a perspective on applications of separations that can make a great difference in biorefineries, by significantly reducing the costs and thus making the processes competitive without subsidies. A parallel is drawn between bio-refinery and petro-refinery, to highlight the specific separation challenges encountered in biorefineries and point out the impact of separations on the total costs. Existing and foreseen separations in biorefineries are reviewed, and the upcoming challenges in the bio-domain (additional to current fossil) are identified. Relevant industrial examples are provided to illustrate the tremendous eco-efficiency benefits of well-designed separation processes based on process intensification principles (e.g. reactive separations, dividing-wall column, affinity and trigger-enhanced separations). These examples also illustrate the low sustainability of several bio-separations currently practiced, in terms of high relative energy requirements, large amounts of gypsum co-production and/or excess use of caustic.     

生物质成型燃料技术及应用前景

分析了现国内生物质电厂集中存在的燃料问题,而生物质成型燃料能够解决秸秆运输、储存、防火等问题,具有广阔的发展前景。对比介绍了生物质成型技术,分析生物质成型燃料的燃料特性。结果表明,生物质成型燃料可以改善燃烧特性,燃烬时间长,有利于提高生物质灰熔点。     

Synthesis and parameter optimization of a combined sugar and ethanol production process integrated with a CHP system

The combined sugar and ethanol production process from sugar cane is a paradigmatic application for energy integration strategies because of the high number of hot and cold streams involved, the external hot utility requirement at two temperature levels for juice evaporation and crystallization, and the electricity demand for juice extraction by milling. These conditions make it convenient to combine the sugar-cane process with a CHP system fuelled by bagasse, the main by-product from juice extraction. The strategies, tools and expertise on energy integration developed separately by the research teams authoring this paper are applied here jointly to optimize the synthesis and the design parameters of the process and of the total site starting from the basic idea of dissociating the heat exchanger network design problem from the total site synthesis problem. At first the minimization of the external heat requirement for the process alone is pursued and results show that a one third reduction can be achieved by optimal heat integration. Then the use of the by-product bagasse for on-site power generation is considered and two bagasse-fuelled CHP systems are optimized along with some parts of the sugar and ethanol production process in order to obtain maximum total site net power. Results show a variety of interesting scenarios of combined sugar, ethanol and electricity production plants with considerably high electricity output.     

Exergetic evaluation of biomass gasification

Biomass has great potential as a clean, renewable feedstock for producing modern energy carriers. This paper focuses on the process of biomass gasification, where the synthesis gas may subsequently be used for the production of electricity, fuels and chemicals. The gasifier is one of the least-efficient unit operations in the whole biomass-to-energy technology chain and an analysis of the efficiency of the gasifier alone can substantially contribute to the efficiency improvement of this chain. The purpose of this paper is to compare different types of biofuels for their gasification efficiency and benchmark this against gasification of coal. In order to quantify the real value of the gasification process exergy-based efficiencies, defined as the ratio of chemical and physical exergy of the synthesis gas to chemical exergy of a biofuel, are proposed in this paper. Biofuels considered include various types of wood, vegetable oil, sludge, and manure. In this study, exergetic efficiencies are evaluated for an idealized gasifier in which chemical equilibrium is reached, ashes are not considered and heat losses are neglected. The gasification efficiencies are evaluated at the carbon-boundary point, where exactly enough air is added to avoid carbon formation and achieve complete gasification. The cold-gas efficiency of biofuels was found to be comparable to that of coal. It is shown that the exergy efficiencies of biofuels are lower than the corresponding energetic efficiencies. For liquid biofuels, such as sludge and manure, gasification at the optimum point is not possible, and exergy efficiency can be improved by drying the biomass using the enthalpy of synthesis gas.     

Evaluation of hydrogen production methods using the Analytic Hierarchy Process

In this paper, seven common hydrogen production processes are evaluated using the Analytic Hierarchy Process (AHP) in respect to five criteria. The processes to be evaluated are steam methane reforming (SMR), partial oxidation of hydrocarbons (POX), coal gasification (CG), biomass gasification (BG), the combination of photovoltaics and electrolysis (PV–EL), the combination of wind power and electrolysis (W–EL) and the combination of hydropower and electrolysis (H–EL). The selected criteria that were used in the evaluation, for each of the seven hydrogen production processes are CO₂ emissions, operation and maintenance costs, capital cost, feedstock cost and hydrogen production cost. According to the evaluation, the processes that combine renewable energy sources with electrolysis (PV–EL, W–EL and H–EL) rank higher in classification than conventional processes (SMR, POX, CG and BG).     

Biomass gasification for decentralized power generation: The Indian perspective

This article attempts to highlight the technical and economical issues related to decentralized power generation in India using biomass gasification. Biomass-based energy has several distinct advantages such as wide availability and uniform distribution that puts it ahead among the renewable energy options for India. The estimated potential of power generation through renewable sources in India is 85 GW with biomass power contributing approximately 20 GW. Especially, in the remote areas and hilly terrains of India, biomass gasification-based power generation offers a highly viable solution for meeting energy demands of small villages and hamlets, which would not only make them independent but will also reduce burden on state electricity boards. This paper reviews various technical options for biomass gasification-based low-, medium- and large-scale power generation. We essentially discuss the merits and demerits (operational and other problems) of different systems. Further, we also deal with economics of these systems and discuss principal factors influencing the viability of the biomass-based power generation. Finally, we review some case studies of biomass-based power generation for meeting energy needs, both thermal and electrical.     

Agricultural biogas plants – A systematic analysis of strengths,weaknesses, opportunities and threats

In this paper, we discuss the prospects of agricultural biogas plants. We conducted an integrated SWOT–AHP analysis for such plants in Austria in order to identify strengths, weaknesses, opportunities and threats (SWOT factors), and to weight the factors identified based on expert judgments, calculated according to the Analytic Hierarchy Process (AHP) method. The results show that financial aspects are dominant in three of the four SWOT categories. Technological aspects and issues regarding utilization seem to play a relatively minor role. Factors that are not directly under the control of plant operators are currently perceived as crucial for the success of agricultural biogas plants. We conclude that such plants will only succeed in contributing to sustainable energy supply goals when economic and political conditions are favorable over the long term.     

基于AHP的实用中长期电力负荷预测最优综合模型

针对中长期电力负荷预测特点,提出一种基于AHP（层次分析法）的中长期电力负荷预测最优综合模型。以历史数据的拟合精度、预测结果与未来经济社会发展的一致性、预测者对模型的信赖度为目标准则;通过自适应进化规划和判断矩陈的方法确定综合模型的最优权重。基于AHP的最优综合模型不令依靠科学计算,而且也考虑了专家经验,将基于AHP的最优综合模型的预测结果与传统综合模型的预测结果相比,误差较小,精度较高,在实用中取得了满意的结果。